Prenatal diagnosis: foretelling the quality of life.

Screening for most genetic risks will eventually be possible through analysis of chromosomal aberrations. But social or religious factors may impede the applications of scientific progress.

DNA technology has revolutionized the laboratory diagnosis of genetic disease. It has also provided new perspectives for the detection of very minute chromosomal aberrations which are invisible under the microscope. In the near future DNA probes for specific parts of each human chromosome will facilitate large-scale prenatal diagnosis in women at risk of giving birth to offspring with a congenital malformation or genetic disease. They will also contribute to the elucidation of the causes of hitherto unexplained mental retardation and physical handicap.

At present some 750 disease genes have been identified. This has widened the scope of the prenatal diagnosis of genetic diseases and the detection of gene-mutation carriers, who are usually healthy themselves but may have an increased risk of producing affected children. DNA technology also offers new perspectives for the development of animal models for human diseases, making it possible to study pathogenesis and work out new therapeutic strategies. The latter will be especially important in the various types of cancer for which specific chromosomal aberrations and gene defects have been identified both in germ cells and somatic cells.

These techniques of diagnosis and carrier identification form the basis for genetic counselling to couples who on the …